Metal alloy.



. M AL ALLOY.

1,052,423. No Drawing.

"ipeciflcation of Letters Patent. Application filed July 20, 1912. SerialNo. 710,59}.

ELWOOD mums. or koxomo; nmuiua I Patented Apr. 1, 1913.

To all whom itmcy concern:

Be it known that I, ELwooo HAYNns, a citizen of the United States, and a resident of Kokomo, in the county of Howard and State of Indiana, have invented certain new and useful Improvements in Metal Alloys; and I do hereby declare that the following is a full, clear, and exact description thereof.

This invention relates to a metal alloy more articularly designed for use in the manu acture of articles, such as tools or cutting implements, wherein are re uired the qualities ofnhardness, toughness nd elas- 'ticity, together with the capacity of taking a high polish and receiving and retaining a sharp cutting edge.

Among the objects of my invention are to produce. ametal capable of production on a commercial scale and at a moderate cost and having the properties above set forth, and which is particularly adapted for use as a substitute for steel for makin cutting im plements, machine tools and t e like. In my prior- Patent No. "873,745, issued December 17, 1907, I have described a binary alloy, consisting of cobalt and chromium, or other metal of the chromium group allied with chromium, or having properties like mosphere and fumes occurrin s capable of being forged, h 40 those of chromium; such metals of the chr0- mium group embracing, in addition to chromium, tungsten, molybdenum and uranium. The binary alloy described in said patent possesses a high degree of hardness and toughness adapting it for usein Jthe manufacture of edged tools, cutlery and the like, has ahigh degree of resistance to oxidizationand the corrosive-action of the attherein, and amniered, or otherwise worked into various forms of in struments and articles.

I have discovered that" ternary and quaternary" alloys, consisting of cobalt and two or more metals ofthe chromium group,\possess particular value-{and qualities in many respects superior tofthose of the binary alloy setforth in'said patent above mentioned. I have discovered, moreover, that such ternary alloys possess very valuable properties when composed of cobalt, chromium and tungsten,

or cobalt, chromium and molybdenum, and that the quaternary alloys have also very,

- valuable properties when composed of cobalt,

chromium, tun sten and molybdenum.

An alloy m i e in accordance with my in- Vention is composed of cobalt, chromium and one of the other metals of the chromium group, combined in the pro ortions substantially as hereinafter speci e l. The metals included in the chromium group, towhich reference has been made, embrace, in addition to chromium, tungsten, molybdenum,-

and uranium. My experiments up to the present time have led meto prefer, of the metals of the chromium group, tungsten and molybdenum, as possessing the most desirable qualities as constituents of my alloy for the general purposes and uses intended, although it may be found that for dilferent uses the other metal of the chromium group, to wit, uranium, may be employed to advantage, as one of the constituents of the alloy.

An allo of cobalt, chromium and tungsten, which I have found to possess the desired properties for many articles or uses, contains chromium in a percentage of fifteen per cent. (15%) or less, and tungsten in a percentage of fifteen per cent. (15%) or less. Such ternary alloys may be readily forged at aired heat. Moreover, by using a considerable amount of care an alloy containing sixty-five per cent. (65%) of cobalt, fifteen per cent. (15%) of chromium and twenty per cent. (20%) of tungsten can be forged to a considerable degree. All such ternary alloys possess'val-uable properties in addition to those of the binary, or cobalt and chromium alloys, for many urposes, on account of .the tungsten constituent, which gives to the alloy increased hardness and toughness, as well as. a superior capacity to receive a sharp cutting edge and to retain the same under the most severe usage.

In a ternary alloy of cobalt, chromium and tungsten, if the chromium constituent equal twentyfive per cent. (25%) and the tungsten .be'present in the proportion of five per cent. (5%) the alloy is particularly suitable for wood-cutting tools, table knives and other cutlery. Such an alloy forges readily, shows a fine fracture, is very strong and elastic, and takes a fine cutting edge. The corresponding alloy, containing molybdenum in place of the tungsten, possesses similar properties.

' out No; 873,745 in being capable of taking a high and durable luster, and of resisting the.

oxidizing and corrosive action of moisture, acids, the atmosphere and corrosive fumes I commonly occurring in the atmosphere.

If in a ternary alloy of cobalt, chromium and tungsten, the tungsten constituent be increased from fifteen per. cent. (15%) to say fifty per cent. (50%), the alloy becomes harder with increasing percentage of tungsten, and the same cannot be successfully forged after the tungsten constituent exceeds twenty-five per cent. (25%). A ternary alloy, containing from twenty-five per cent. (25%) to fifty per cent. (50%) of tungsten, fifteen per cent. (15%) of chromium, the remainder being cobalt, makes excellent lathe tools, ossessing to a high degree the qualities 0 hardness, toughness, and capacity of receiving and retaining a very sharp cutting edge. I have found that such lathe tools possess hardness, toughness and cutting qualities to a degree making them much superior to any steel lathe tools now produced. Moreover, such alloy is found to be capable or resisting to a large degree the corrosive action of moisture and the atmosphere. When the tungsten constituent exceeds twent -five per cent. (25%), the alloy becomes su ciently hard to readily scratch glass, and will even mark or score rock crystal. With percentages of twenty-five (25) to fifty (50) of the tungsten constituent, the ternary alloy, while not capable of being forged, may be readily fused, and lathe tools or other articles may be readily made by casting the same in the desired form and finishing by a suitable grinding operation. When the tungsten constituent in the ternary alloy exceedsfifty er cent. (50%) the alloy becomes very di cult to fuse, or fuses under very high tem eratures, such as are usually obtainable only by the use of the electric are, but the alloy containing such higher percentages of tungsten, While somewhat brittle, makes excellent lathe tools.

In the case of the ternary alloy, in which the molybdenum is used in place of tungsten,'the same general conditions and characteristics, hereinbefore referred to in connect-ion F with the cobalt-chromium-tungsten alloys. are found to exist; excepting that the alloy reaches a condition in which it cannot be successfully forged when the percentage of molybdenum is somewhat smaller than is the case if tungsten is used as the third constituent. When the molybdenum constituent-in such alloy is made to exceed twentyfive per cent. (25%) the alloy .is very hard, and if the proportion of molybdenum does not exceed thirty per cent: (30%) the alloy 'is not only very hard but likewise very tough and strong, and may be used with great advantage for lathe tools. When the percentage of molybdenum is as high as forty per cent. (40%) or more, the alloy becomes exceedingly hard and quite brittle. It will cut persistently into glass, and a sharp corner of the metal, when drawn back and forth over the surface of a quartz crystal, jwill rapidly cuta deep groove in that material.

W'ith respect to the ternary alloys of cobalt and chromium, with either tungsten or molybdenum as the third constituent, an increase in the percentage of t-he chromium.

constituent will give greater hardness and brittleness to these alloys even when they contain the tungsten or molybdenum eonstituents in the lower percent-ages. I have found, however, that the alloys described possess considerable toughness when the chromium constituent is present to the extent of as much as forty per cent. (40%), and if the tungsten or molybdenum constituent be low, that alloys useful for practical purposes may contain even a higher percentage of chromium. So far as my experiments have extended, moreover, I have found that advantageous results are obtained when the tungsten or molybdenum constituent is present in the alloy in the proportion, to the entire alloy, of froln five per cent. (5%) to eighty per cent. (80%). In View of the fact, however, that an increase of the percentage, either of the chromium constituent, or of the tungsten or molybdenum contle, a smaller proportionate quantity of chromium will desirably be used when the proportion of tungsten or molybdenum is relatively large and vice versa. This is indicated by the examples above given of ternary alloys suitable in one instance for cutlery and the like and, the other instance, for lathe tools; to wit, in the first instance, twenty-five per cent. (25%) of chromium and five per cent. (5%) of tungsten (or molybdenum) with a corresponding percentage of the cobalt constituent, and, in the second instance, fifteen per cent. (15%) of chromium, and twenty-five per cent. (25%) of'tungsten (or molybdenum) with a. corresponding percentage of cobalt.

By making a quaternary alloy consisting of cobalt, chromium, and two of the other metals of the chromium group, namely, both tungsten and molybdenum, I have discovered that valuable alloys are obtained, such as are particularly, suitable for high-speed lathe tools. For example, I have produced an alloy containing five per cent. (5%) of molybdenum, twenty-five percent... (25%) of tungsten, fifteen per cent. (15%) of chromium and fifty-five per cent. of cobalt. which, after being cast into a bar and made into a lathe tool, affords a tool which will cut cast iron and steel, Without overheating of or injury to the tool, from fifty (50) to one hundred per cent. (100%) faster than a tool made from the best special or high speed steel now produced for such purposes. In the case of such quaternary alloys, in correspondence with the ternary alloys, the chromium constituent may be present in the proportion of from five (5) to eighty per cent. (80%), or the tungsten and molybdenum constituents together may be present in the same proportions of from five (5) to eighty (80) per cent, with such relative proportions of the chromium constituent. on the one hand, and the total quantity of the tungsten and molybdenum constituents, on the other hand, as to prevent an undesirable degree of brittleness in the allov.

l have found, in general, that cobalt, in an alloy with two or more metals of the chromium group, produces a series of useful alloys, throughout a very wide range in the relative proportion of the constituents. l'n the case of admixtures bf many other metals, the hardness rapidly increases with the increase in the proportion of one or more of the constituents, until the alloy becomes so brittle as to be unfit for practical vuse. As, for instance, if copper be alloyed with tin, an increase in the hardness of the alloy takes place, until, when the proportion oftin is materially over ten per cent." (10%),-

the alloy becomes so brittle as to be un for practical use. To the contrary in the case of such other alloys, an increase in either the chromium, tungstenor molybdenum constituent, in the ternary and quaternary alloys referred to, even beyond the proportions her'einbefore generally stated,

(but so far as my experiments have gone, not exactly determined), will not make the alloy too brittle for practical uses. In other words, my tests have shown that, when the constituents of the alloys described are present, within the wide range of relative proportions stated, a series of alloys may be produced having novel and Very valuable properties, and capable of use in the arts with great advantage and benefit.

It is to be understood that small quantities of other metals, or non-metallic sub-.

stances, may be combined with the ternary and quaternary alloys described, such as'will not injuriously afi'ect the nature of such alloys, and which may to some extent modify their properties and render them more suitable for special requirements.

From the above, it will be understood that l have discovered new and usefulternary mium group.

chromium and tungsten.

characteristics, as well as similar properties, whether composed of cobalt, chromium and tungsten; cobalt, chromium and molybdenum; or cobalt, chromium, tungsten and molybdenum. It is also to be understood that any other metal of the chromium'groufi' may be added to the alloy or substituted in the alloy for either one of the metals of the chromium group hereinbefora particularlyspecified.

Inasmuch as an alloy having the same general characteristics may be obtained by embodying cobalt and chromium with either one of the other metals of the chromium group, to wit, tungsten or molybdenum (forming a ternary compound) or with two of such other metals of such chromium group, to wit, "tungsten and molybdenum (formlng a quaternary compound), it is to.

include in a general sense, either one or morevthan one of the specific metals, other than chromium, known or commonly designated as metals of thechromium group.

The quaternary compound herein described constitutes the subject-matter of. a separate application, Serial No. 715,326, filed August 16,1912. I claim as my invention. s 1

l. A metal alloy composed of cobalt and at least two of the metals of the chromium group.

appended claims, is intended-tomean, or to 2. A metal" alloy composed of cobalt,

chromium, chromium.

3. A metal alloy composed of obalt, chromium and one other metal of thg chroand other fmetal allied with it. A metal alloy composed of cobalt-,2

5. A metal alloy composed of chromium and other metal allied with chromium, in the proportion of not'more than sixty per cent (60%) o the metal allied with chromium, the rem inder of the alloy being cobalt and chromium.

6. A metal alloy composed of cobalt,\,

chromium and other metal allied with chromium, in the proportions of from five per cent. (5%) to sixty per cent. (60%) oi. such metal allied with chromium, the re 1320f mainder of the alloy being'- obalt and chromium.

-7. A metal alloy composed of cobalt, v

chromium and one other metal of the cobalt, i

chromium group, in proportionof not more than sixty per cent. (60%) of such metal of the chromium group, the remainder of the ing as my invention I affix my signature in alloy being cobalt and chromium. the presence of two witnesses, this 17th day 10 8. A metal alloy composed of cobalt, of July A. D. 1912.

chromium and tungsten, in proportion of 5 from five per cent. (5%) to sixty per cent. ELWOOD HAYNES (60%) of tungsten, the remainder *of the Witnesses: alloy being cobalt and chromium. BERTIIA B. HAYNES,

In testimony, that I, do claim the forego- HARRY W. LANTERNAN. 

